Karst stratum groutability test analysis method, device, equipment and medium

Abstract

The invention provides a karst stratum rock groutability test analysis method, device, equipment and medium, and relates to the technical field of mine water disaster prevention and control, and the method comprises the steps: obtaining a rock core sample, and obtaining a to-be-grouted rock sample and first pore information of the to-be-grouted rock sample before grouting; the method comprises the following steps: acquiring a first weight and a rock sample length of a to-be-grouted rock sample before grouting, performing a grouting test and slurry initial setting on the to-be-grouted rock sample to obtain a grouted rock sample, and acquiring a second weight of the grouted rock sample; based on the first weight, the rock sample length and the second weight, the linear meter grouting amount of the rock sample to be grouted is determined; acquiring second pore information of the grouted rock sample; and evaluating the groutability of the karst stratum based on the first pore information, the second pore information and the linear meter grouting amount. According to the method, advanced research on the groutability of the target governance layer is realized, and a scientific basis is provided for subsequent ground area governance scheme design, project amount, grouting amount prediction and governance effect verification and evaluation.

Description

Technical Field

[0001] The invention relates to the technical field of mine water hazard prevention and control, and in particular to a method, device, equipment and medium for injectability test analysis of karst strata. Background Art

[0002] More than 50% of my country's coal mines are threatened by karst confined water hazards in the coal seam floor to varying degrees. In recent years, with the continuous reduction and depletion of shallow coal resources, the depth of coal mining has gradually increased, and the threat of karst confined water hazards faced by lower coal mining has become increasingly prominent. In North China alone, more than 60% of coalfields are threatened by coal seam floor confined water hazards to varying degrees. In most areas, the coal seam floor is subject to a large karst water pressure, which can reach 5-7MPa, but the thickness of the impermeable layer between the coal seam and the underlying limestone confined aquifer is 30-50m. In many areas, the thickness of the impermeable layer in the lower coal seam floor is even smaller, only 10-20m. If the region also develops hidden vertical structural channels such as faults and collapse columns, it will cause karst confined water to be directly dislocated to the vicinity of the coal seam or to be conducted to the vicinity of the coal seam floor. As the coal seam is mined, the floor fracture zone and disturbance zone are connected to the hidden structure, which will greatly increase the probability of water inrush during coal seam mining.

[0003] In recent years, well and surface flooding accidents caused by karst confined water have occurred frequently. The hydrogeological conditions in some areas are relatively complex. The development degree of karst fissures and water-conducting structures in the Ordovician limestone karst strata in different areas within the treatment scope varies greatly, and the karst fissures in the top interface area of ​​the Ordovician limestone karst strata are highly heterogeneous, resulting in large differences between the design of the treatment plan and the engineering quantity and the actual construction process, causing great uncertainty in the mine budget and treatment investment, and even requiring changes in the plan and budget additions during the implementation of the project, which has a certain impact on the quality and progress of the entire treatment project. Therefore, in view of this situation, it is necessary to carry out injectability tests in different areas of the treatment scope in advance to obtain injectability evaluation results of the Ordovician limestone karst strata under different treatment areas and different stratum geological conditions, and then clarify the karst fissure development, slurry consumption and other specific parameters of the target layers of the Ordovician limestone karst strata in different areas, so as to provide a scientific basis for the overall scheme design, engineering quantity and investment budget.

[0004] At present, there are several injectability schemes for Ordovician limestone karst formations.

[0005] The injectability assessment is carried out by using the experience of ground regional governance construction in the surrounding areas. The experience of ground regional governance construction in the surrounding areas can provide a certain reference for the injectability assessment of the Ordovician limestone karst strata within the governance scope and the design of ground regional governance schemes. However, the geological characteristics and geological structure development of the strata in different regions and different well fields vary greatly, especially in areas with complex geological conditions and hydrogeological conditions. The karst strata are affected by the paleogeographic sedimentary environment and later tectonic movements, and the primary fissures and fault structures are significantly different. In addition, the internal fissure development, water richness, and water-conducting channels of the Ordovician limestone karst strata are highly heterogeneous, and there are large errors in the injectability assessment based solely on the construction experience of the surrounding areas. It will lead to a substantial increase in the construction party's investment and an extension of the construction period, affecting the subsequent mining and excavation continuation plan of the coal mine.

[0006] It is difficult to lower the casing when drilling to the target layer for injectability assessment through conventional underground drilling (general drilling). The holes to the target layer are distributed in a point manner, and there are difficulties in slag removal. The underground construction space is limited, and it is necessary to coordinate transportation, water, electricity, etc., which has a certain impact on the daily production of the mine. Nighttime construction is prohibited in some areas, the total cost is too high, the construction period is too long, and the economy is poor.

[0007] In conclusion, the existing injectability test analysis methods for Ordovician limestone karst formations have low reliability. Summary of the invention

[0008] The present invention provides a karst stratum injectability test analysis method, device, equipment and medium, which are used to solve the defect of low reliability of the injectability test analysis method of Ordovician limestone karst stratum in the prior art, and to improve the reliability of analyzing the injectability of Ordovician limestone karst stratum.

[0009] The present invention provides a method for testing and analyzing the injectability of a karst formation, comprising: obtaining core samples of a karst formation under different geological conditions in a well field, sampling the core samples at different heights based on a target treatment layer of the karst formation to obtain a rock sample to be grouted; obtaining first pore information of the rock sample to be grouted before grouting; obtaining a first weight and a rock sample length of the rock sample to be grouted before grouting, performing a grouting test and initial setting of slurry on the rock sample to be grouted to obtain a grouted rock sample, and obtaining a second weight of the grouted rock sample; determining a grouting volume per meter of the rock sample to be grouted based on the first weight, the rock sample length, and the second weight; obtaining second pore information of the grouted rock sample; and evaluating the injectability of the karst formation based on the first pore information, the second pore information, and the grouting volume per meter.

[0010] According to the injectability test and analysis method of karst strata provided by the present invention, a grouting test and initial setting of slurry are performed on a rock sample to be grouted to obtain a grouted rock sample, comprising: after drying the rock sample to be grouted, placing it in a test chamber, with the first end and the second end of the test chamber both in an open state; pouring slurry into the test chamber from the first end, and when the slurry in the test chamber reaches a preset ratio, closing the second end, and continuing to pour slurry to increase the pressure in the test chamber until the pressure in the test chamber reaches a set high pressure; stabilizing the pressure of the test chamber to maintain the pressure in the test chamber at the set high pressure until the stabilization time exceeds a preset time; after waiting for the initial setting of the slurry in the test chamber, opening the second end to relieve the pressure of the test chamber, removing the external cement slurry stone body of the grouting rock sample, and obtaining a rock sample after the initial setting of the slurry; drying the rock sample after the initial setting of the slurry to obtain a grouted rock sample.

[0011] According to the injectability test analysis method of karst strata provided by the present invention, the high pressure is set to include 1.5p~2p, and p is the pressure of the coal seam floor of the target treatment layer to withstand the Ordovician limestone water pressure.

[0012] According to the injectability test analysis method of karst strata provided by the present invention, the target treatment layer is determined based on the following steps: observing the detection information set of the well field based on the geological exploration holes of the well field and / or the hydrological observation boreholes of the well field, the detection information set including the karst pressure water level elevation, the coal seam floor position and the Ordovician ash top interface position; calculating the thickness of the coal seam floor aquiclude to be modified and the target treatment layer based on the detection information set combined with the requirements of the Ordovician ash pressure water inrush coefficient of the coal seam floor.

[0013] According to the injectability test analysis method of karst formation provided by the present invention, the second pore information of the grouting rock sample is obtained, including: processing the grouting rock sample, CT scanning and scanning electron microscope scanning to obtain the porosity of the grouting rock sample; based on the CT scanning result of the grouting rock sample, three-dimensional modeling of the grouting rock sample is performed to obtain the three-dimensional model of the grouting rock sample, and the three-dimensional model of the grouting rock sample includes the pore distribution characteristics, pore and fracture connectivity status and pore and fracture filling status inside the grouting rock sample; based on the porosity, pore distribution characteristics, pore and fracture connectivity status and pore and fracture filling status of the grouting rock sample, the second pore information is obtained.

[0014] According to the injectability test analysis method of karst formation provided by the present invention, the rock samples to be grouted include rock samples to be grouted at a first elevation, rock samples to be grouted at a second elevation, and rock samples to be grouted at a third elevation. Based on the target treatment layer of the karst formation, core samples are sampled at different elevations to obtain rock samples to be grouted, including: taking the target treatment layer as the first elevation, sampling the core samples based on the first elevation to obtain the rock samples to be grouted at the first elevation; taking the sum of the target treatment layer and the set height as the second elevation, sampling the core samples based on the second elevation to obtain the rock samples to be grouted at the second elevation; taking the difference between the target treatment layer and the set height as the third elevation, sampling the core samples based on the third elevation to obtain the rock samples to be grouted at the third elevation.

[0015] According to the injectability test analysis method of karst formation provided by the present invention, the grouting volume per meter of the rock sample to be grouted includes the grouting volume per meter of multiple rock samples to be grouted at different elevations, and after determining the grouting volume per meter of the rock sample to be grouted based on the first weight, the rock sample length, and the second weight, the method further includes: calculating the average value of the grouting volume per meter of the multiple rock samples to be grouted at different elevations to obtain the average grouting volume per meter; and evaluating the injectability of the karst formation in the area where the core sample is located based on the first pore information, the second pore information, and the average grouting volume per meter.

[0016] The present invention also provides a karst stratum injectability test and analysis device, comprising a sampling module, a pore measurement module, a grouting module and an evaluation module: the sampling module is used to obtain core samples of karst strata under different geological conditions in a well field, and the core samples are sampled at different heights based on the target treatment layer of the karst stratum to obtain rock samples to be grouted; the pore measurement module is used to obtain first pore information of the rock samples to be grouted before grouting; the grouting module is used to obtain a first weight and a rock sample length of the rock sample to be grouted before grouting, and perform a grouting test and initial setting of slurry on the rock sample to be grouted to obtain a grouted rock sample, and obtain a second weight of the grouted rock sample; the grouting module is also used to determine the grouting amount per meter of the rock sample to be grouted based on the first weight, the rock sample length and the second weight; the pore measurement module is also used to obtain second pore information of the grouted rock sample; the evaluation module is used to evaluate the injectability of the karst stratum based on the first pore information, the second pore information and the grouting amount per meter.

[0017] The present invention also provides an electronic device, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, any of the above-mentioned injectability test analysis methods for karst formations is implemented.

[0018] The present invention also provides a non-transitory computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the injectability test analysis method of any of the above karst formations is implemented.

[0019] The present invention provides a method, device, equipment and medium for testing and analyzing the injectability of karst formations. Core samples of karst formations under different geological conditions in a well field are obtained, and the core samples are sampled at different heights based on a target treatment layer of the karst formation to obtain rock samples to be grouted; first pore information of the rock samples to be grouted before grouting is obtained; a first weight and a rock sample length of the rock samples to be grouted before grouting are obtained, a grouting test and initial setting of slurry are performed on the rock samples to be grouted to obtain a grouted rock sample, and a second weight of the grouted rock sample is obtained; based on the first weight, the rock sample length and the second weight, a meter-long grouting volume of the rock sample to be grouted is determined; second pore information of the grouted rock sample is obtained; and the injectability of the karst formation is evaluated based on the first pore information, the second pore information and the meter-long grouting volume. The present invention conducts grouting tests on rock samples to be grouted under different geological conditions and compares the pore and fissure characteristics of rock samples before and after grouting, thereby realizing an advance study on the injectability of the target treatment layer, and providing a scientific basis for the subsequent design of ground area treatment schemes, engineering quantity, grouting quantity estimation, treatment effect verification and evaluation. The present invention obtains the consumption of dry materials for grouting per meter of the target stratum for karst strata treatment under different geological conditions by analyzing the first pore information, the second pore information and the grouting volume per meter, clarifies the distribution characteristics of pores and fissures inside the karst strata under different geological conditions, the connectivity status and the filling and blocking of pores and fissures after grouting, realizes the injectability evaluation of Ordovician limestone karst strata under different geological conditions, and can accurately obtain the injectability of Ordovician limestone karst strata in different areas within the treatment range and the measured data related to the grouting effect and intuitive visualization information. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic flow chart of the injectability test analysis method of karst strata provided by the present invention.

[0022] Figure 2 It is a schematic flow chart of the grouting test provided by the present invention.

[0023] Figure 3 It is a CT scanning result of the rock sample to be grouting and a schematic diagram of a three-dimensional model of the rock sample to be grouting provided by the present invention.

[0024] Figure 4 It is a CT scanning result of the grouting rock sample and a schematic diagram of a three-dimensional model of the grouting rock sample provided by the present invention.

[0025] Figure 5It is a structural schematic diagram of the injectability test and analysis device for karst strata provided by the present invention.

[0026] Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention.

[0027] Reference numerals: 10: 4-inch union joint; 20: slurry channel; 30: first end; 40: test chamber; 50: second end; 60: pressure relief port. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] In view of the current situation that there are certain differences between the injectability evaluation of karst formations, the selection of treatment parameters, the design of treatment plans and the actual situation of the formations when the ground area of ​​Ordovician limestone karst water hazards is advanced under the conditions of complex geological conditions, developed structures and obvious zoning of geological characteristics of the formations within the treatment scope; during the implementation of the project, the injectability evaluation of karst formations and the filling and blocking states of the fractures before and after grouting transformation cannot be directly compared, and the analysis of injectability and grouting effect lacks a definite and visual evaluation basis. It is very important to select a technical solution for injectability evaluation of the formation. The present invention provides a method for analyzing injectability of Ordovician limestone karst formations.

[0030] Combine the following Figure 1-Figure 6 The present invention describes the injectability test analysis method, device and electronic equipment of karst strata.

[0031] Figure 1 FIG. 1 is a flow chart of the injectability test analysis method of karst formation provided by the present invention, such as Figure 1 As shown, the injectability test analysis method for karst formations includes steps S100 to S600, and each step is specifically as follows.

[0032] S100: obtaining core samples of karst strata under different geological conditions in the well field, sampling the core samples at different heights based on the target treatment layer of the karst stratum, and obtaining rock samples to be grouting.

[0033] The present invention is a formation injectability test analysis method, which is not only applicable to the Ordovician limestone karst formation, but also applicable to the injectability test analysis of all karst formations such as the Taihu limestone karst formation and the Hanhui limestone karst formation. The present invention is described by taking the Ordovician limestone karst formation as an example.

[0034] According to the previous geological exploration boreholes and hydrological observation boreholes of the well field, hydrogeological supplementary exploration boreholes are arranged. The reliability of the earlier geological exploration boreholes and hydrological observation boreholes is poor (no detailed and comprehensive data on formations, water levels, etc.). At the same time, due to the changes in hydrogeological conditions over time, the earlier geological exploration boreholes and hydrological observation boreholes are greatly different from the current hydrogeological conditions, and the research significance is low. Therefore, it is necessary to add ground supplementary exploration boreholes to obtain the latest formation geological and hydrological data, and obtain core samples of Ordovician limestone karst formations under different geological conditions.

[0035] The target treatment layer is determined according to the detection information set of the well field. Different elevations are delineated with the target treatment layer as the center. According to the elevations of different heights, the core samples are sampled at different height layers to obtain multiple rock samples to be grouting.

[0036] S200: Acquire first pore information of the rock sample to be grouting before grouting.

[0037] The rock sample to be grouted is sent to the laboratory for processing, scanning and modeling to obtain the first pore information of the rock sample to be grouted before grouting. The first pore information includes the porosity of the rock sample to be grouted, the pore distribution characteristics inside the rock sample to be grouted, the pore and fracture connectivity state and the pore and fracture filling state.

[0038] For example, the rock sample to be grouted is processed, CT scanned and scanned by scanning electron microscope. The porosity of the rock sample to be grouted is obtained according to the CT scanning results and the scanning electron microscope scanning results. The rock sample to be grouted is three-dimensionally modeled according to the CT scanning results of the rock sample to be grouted to obtain a three-dimensional model of the rock sample to be grouted. The three-dimensional model of the rock sample to be grouted includes the pore distribution characteristics, pore and fracture connectivity status and pore and fracture filling status inside the rock sample to be grouted. For example, the three-dimensional model of the rock sample to be grouted includes image information such as the pore and fracture distribution and connectivity characteristics inside the rock sample to be grouted.

[0039] S300: obtaining a first weight and a length of the rock sample to be grouted before grouting, performing a grouting test and initial setting of the slurry on the rock sample to be grouted to obtain a grouted rock sample, and obtaining a second weight of the grouted rock sample.

[0040] The test device (including the slurry delivery switch device, the slurry channel and the test chamber) is used to simulate the filling, compaction and crack sealing of the slurry in the pores and cracks of the rock sample to be grouted, and the grouting volume per meter in the Ordovician limestone karst formation under the corresponding geological conditions is calculated.

[0041] Before grouting, the first weight and length of the rock sample to be grouted are measured. After grouting, the second weight of the grouted rock sample is measured.

[0042] S400: Determine the grouting volume per meter of the rock sample to be grouted based on the first weight, the length of the rock sample and the second weight.

[0043] The grouting volume per meter of the rock sample to be grouted is calculated based on the measured first weight, the length of the rock sample and the second weight.

[0044] ; in, is the grouting volume per meter, in tons per meter (t / m), is the length of the rock sample, in m, is the first weight, in kg, is the second weight, in kg.

[0045] S500: Acquire second pore information of the grouting rock sample.

[0046] The grouting rock samples are sent to the laboratory for processing, scanning and modeling to obtain the second pore information of the grouting rock samples after grouting. The second pore information includes the porosity of the grouting rock samples and the pore distribution characteristics inside the grouting rock samples, the pore-crack connectivity state and the pore-crack filling state.

[0047] S600: Evaluate the injectability of the karst formation based on the first pore information, the second pore information and the grouting volume per meter.

[0048] According to the first pore information and the second pore information, the pore changes and pore and fracture filling states of the rock sample to be grouted and the rock sample already grouted before and after grouting are compared.

[0049] Figure 3 The CT scanning results of the rock sample to be grouting and the three-dimensional model of the rock sample to be grouting. Figure 4 The CT scan results and 3D model of the grouting rock sample are shown in Figure 1. The red part is the pores and the blue part is the solid skeleton inside the rock sample.

[0050] Compare Figure 3 and Figure 4 It can be seen that the pores of the rock samples to be grouted are large and well connected, and the distribution range of pores and fissures is wide. The pores of the grouted rock samples are small, the connectivity is poor, and the area and distribution range of pores and fissures are much smaller than before grouting. It can be seen that after grouting, the karst pores and fissures in the original karst samples of the target stratum for treatment are well filled and the fissures are blocked, which can significantly reduce the pore and fissure space of the target treatment stratum. The greater the difference between the first pore information and the second pore information, the more obvious the improvement of the pores in the target treatment stratum before and after grouting, and the better the injectability of the karst formation. At the same time, the larger the grouting volume per meter, the better the injectability of the karst formation.

[0051] Furthermore, the pore filling degree of the rock sample to be grouted is calculated according to the porosity of the rock sample to be grouted and the porosity of the rock sample already grouted. Porosity filling degree = porosity of the rock sample to be grouted - porosity of the rock sample already grouted. The greater the pore filling degree, the better the injectability of the karst formation.

[0052] The injectability test analysis method of karst formation provided by the present invention obtains core samples of karst formation under different geological conditions of the well field, samples the core samples at different heights based on the target treatment layer of the karst formation, obtains the rock sample to be grouted; obtains the first pore information of the rock sample to be grouted before grouting; obtains the first weight and rock sample length of the rock sample to be grouted before grouting, performs grouting test and initial setting of slurry on the rock sample to be grouted, obtains the grouted rock sample, obtains the second weight of the grouted rock sample; determines the grouting amount per meter of the rock sample to be grouted based on the first weight, the rock sample length and the second weight; obtains the second pore information of the grouted rock sample; and evaluates the injectability of the karst formation based on the first pore information, the second pore information and the grouting amount per meter. The present invention realizes the advance study of the injectability of the target treatment layer by performing grouting test on the rock samples to be grouted under different geological conditions and comparing the pores and fissures of the rock samples before and after injection, and provides a scientific basis for the subsequent design of ground area treatment schemes, engineering quantity, grouting amount estimation, treatment effect verification and evaluation. The present invention obtains the per-meter grouting dry material consumption of the target stratum for karst stratum treatment under different geological conditions by analyzing the first pore information, the second pore information and the per-meter grouting amount, clarifies the distribution characteristics of pores and fissures inside the karst stratum under different geological conditions, the connectivity status and the filling and sealing of pores and fissures after grouting, realizes the injectability evaluation of Ordovician limestone karst strata under different geological conditions, and can accurately obtain the injectability of Ordovician limestone karst strata in different areas within the treatment scope and the measured data related to the grouting effect and intuitive and visualized information.

[0053] Based on the above embodiments, a grouting test and initial setting of slurry are performed on a rock sample to be grouted to obtain a grouted rock sample, including: placing the dried rock sample to be grouted into a test chamber, with the first end and the second end of the test chamber both in an open state; pouring slurry into the test chamber from the first end, and when the slurry in the test chamber reaches a preset ratio, closing the second end, and continuing to pour slurry to increase the pressure in the test chamber until the pressure in the test chamber reaches a set high pressure; stabilizing the pressure of the test chamber to maintain the pressure in the test chamber at the set high pressure until the stabilization time exceeds a preset time; after waiting for the initial setting of the slurry in the test chamber, opening the second end to relieve the pressure of the test chamber, removing the external cement slurry stone body of the grouting rock sample, and obtaining a rock sample after the initial setting of the slurry; drying the rock sample after the initial setting of the slurry to obtain a grouted rock sample.

[0054] The set high pressure includes 1.5p~2p, and p is the pressure of the coal seam floor in the target treatment layer to withstand the Ordovician ash water pressure.

[0055] The unit of p is MPa. The test device includes a grouting effect simulation test device, which is used to carry out a rock sample fracture grouting filling simulation test. Figure 2 As shown, the specific steps include the following steps.

[0056] (1) Dry the rock sample to be grouting. Measure the length of the rock sample to be grouting after drying. Weigh the rock sample to be grouting to obtain a first weight.

[0057] (2) Fully open the first end 30 of the test chamber (e.g., gate valve No. 1), slightly open the second end 50 of the test chamber (e.g., gate valve No. 2), and place the dried rock sample to be grouting into the test chamber 40.

[0058] (3) Connect the slurry channel 20 to the switch 10 (for example, a 4-inch union joint), and adjust the type and specific gravity of the slurry. For example, the slurry type is cement single-liquid slurry, and the slurry specific gravity specifically includes 1.1 to 1.5 g / cm 3 , select the slurry density according to the actual situation on site, for example, the slurry density is 1.2g / cm 3 Then, grouting is carried out from the first port to the test chamber according to the preset grouting rate. The preset grouting rate includes 60L / min.

[0059] (4) When the slurry in the test chamber reaches the preset ratio, indicating that the test chamber is nearly full, the second end is closed. Continue to pour slurry into the test chamber to gradually increase the pressure in the test chamber until the pressure in the test chamber reaches the set high pressure. Assuming that the coal seam floor in the treatment area (target treatment layer) is subjected to the Ordovician ash water pressure of p MPa, the high pressure is set to 1.5p~2p.

[0060] The present invention determines the set high pressure that the pressure in the test chamber can reach according to the Ordovician lime water pressure borne by the coal seam bottom plate of the target treatment layer, simulates the stress conditions of the target treatment layer during the actual grouting process, and improves the accuracy and scientificity of the grouting test.

[0061] (5) Reduce the opening of the first end of the test chamber, slowly pour grout into the test chamber to stabilize the pressure of the test chamber, and stop grouting until the pressure reaches a preset time (for example, 30 minutes). Wait for the slurry in the test chamber to initially set, and set the waiting time according to the initial setting time of the grouting liquid, for example, the waiting time is 10 to 16 hours. After the slurry in the test chamber initially sets, slowly open the second end of the test chamber (for example, gate valve No. 2), and slowly release the pressure in the test chamber through the pressure relief port 60, for example, the pressure in the test chamber is reduced to 0 MPa. Take out the rock sample that has completed initial setting. Clean the external cement slurry stone body of the rock sample that has completed initial setting to obtain the injected rock sample.

[0062] (6) Dry the injected rock sample and weigh it to obtain the second weight of the injected rock sample.

[0063] The present invention accurately simulates the grouting process of karst strata and the filling state of slurry in the original karst strata by conducting grouting tests and initial setting of slurry on rock samples to be grouted, providing a scientific basis for the subsequent design of ground area management plans, engineering quantity, grouting volume estimation, and management effect verification and evaluation.

[0064] Based on the above embodiment, the target treatment layer is determined based on the following steps: based on the detection information set of the well field observed by the geological exploration holes and / or the hydrological observation boreholes of the well field, the detection information set includes the karst pressure water level elevation, the coal seam floor position and the Ordovician ash top interface position; based on the detection information set combined with the requirements of the coal seam floor Ordovician ash pressure water inrush coefficient, the thickness of the coal seam floor aquiclude to be modified and the target treatment layer are calculated.

[0065] The geological exploration holes of the well field include the preliminary geological exploration holes and supplementary geological exploration holes of the well field under different geological conditions. The hydrological observation holes of the well field include the preliminary hydrological observation holes and supplementary hydrological observation holes of the well field under different geological conditions. The karst pressure water level elevation, coal seam floor position and Ordovician ash top interface position of the well field are observed according to the geological exploration holes and / or the hydrological observation holes of the well field, and then the thickness of the coal seam floor aquiclude to be transformed and the target treatment layer are calculated in combination with the requirements of the Ordovician ash pressure water inrush coefficient of the coal seam floor.

[0066] The present invention observes the detection information set of the well field through the geological exploration holes of the well field and / or the hydrological observation boreholes of the well field, thereby improving the accuracy, real-time and reliability of determining the detection information set, which is conducive to improving the accuracy of subsequent determination of the target governance layer.

[0067] Based on the above embodiment, the second pore information of the grouting rock sample is obtained, including: processing the grouting rock sample, CT scanning and scanning electron microscope scanning to obtain the porosity of the grouting rock sample; based on the CT scanning result of the grouting rock sample, three-dimensional modeling of the grouting rock sample is performed to obtain a three-dimensional model of the grouting rock sample, and the three-dimensional model of the grouting rock sample includes the pore distribution characteristics, pore and fracture connectivity status and pore and fracture filling status inside the grouting rock sample; based on the porosity, pore distribution characteristics, pore and fracture connectivity status and pore and fracture filling status of the grouting rock sample, the second pore information is obtained.

[0068] The grouting rock sample is processed, CT scanned and SEM scanned. The porosity of the grouting rock sample is obtained according to the CT scanning results and SEM scanning results. The grouting rock sample is 3D modeled according to the CT scanning results of the grouting rock sample to obtain a 3D model of the grouting rock sample. The 3D model of the grouting rock sample includes the pore distribution characteristics, pore-crack connectivity and pore-crack filling status inside the grouting rock sample.

[0069] Furthermore, the three-dimensional model of the rock sample to be grouted is compared with the three-dimensional model of the grouted rock sample, the porosity changes of the rock sample before and after grouting are analyzed, and visual image data of the slurry filling condition inside the grouted rock sample are obtained.

[0070] The present invention realizes accurate acquisition of the porosity of the grouting rock sample through CT scanning and scanning electron microscope scanning.

[0071] Based on the above embodiment, the rock samples to be grouted include rock samples to be grouted at a first elevation, rock samples to be grouted at a second elevation, and rock samples to be grouted at a third elevation. Based on the target treatment layer of the karst formation, core samples are sampled at different heights to obtain rock samples to be grouted, including: taking the target treatment layer as the first elevation, sampling the core samples based on the first elevation to obtain rock samples to be grouted at the first elevation; taking the sum of the target treatment layer and the set height as the second elevation, sampling the core samples based on the second elevation to obtain rock samples to be grouted at the second elevation; taking the difference between the target treatment layer and the set height as the third elevation, sampling the core samples based on the third elevation to obtain rock samples to be grouted at the third elevation.

[0072] After determining the target governance layer, take the target governance layer b as the first elevation (center line). Determine the second and third elevations according to the set height. For example, if the set height is 5m, the second elevation is b+5m and the third elevation is b-5m.

[0073] Sampling was carried out at b+5m, b-5m and b respectively to obtain the rock sample to be grouting at the first elevation, the rock sample to be grouting at the second elevation and the rock sample to be grouting at the third elevation.

[0074] The present invention determines the first elevation, the second elevation and the third elevation according to the target treatment layer, realizes uniform sampling of core samples, and improves the accuracy of rock samples to be grouting.

[0075] Based on the above embodiments, the grouting volume per meter of the rock sample to be grouted includes the grouting volume per meter of multiple rock samples to be grouted at different elevations. After determining the grouting volume per meter of the rock sample to be grouted based on the first weight, the rock sample length and the second weight, the method also includes: calculating the average value of the grouting volume per meter of the multiple rock samples to be grouted at different elevations to obtain the average grouting volume per meter; and evaluating the injectability of the karst formation in the area where the core sample is located based on the first pore information, the second pore information and the average grouting volume per meter.

[0076] For example, the grouting volume per meter of the rock sample to be grouted includes the grouting volume per meter of the rock sample to be grouted at the first elevation (Q1), the grouting volume per meter of the rock sample to be grouted at the second elevation (Q2), and the grouting volume per meter of the rock sample to be grouted at the third elevation (Q3).

[0077] Calculate the average grouting volume per meter of multiple rock samples at different elevations to obtain the average grouting volume per meter (Q平均 ). For example, Q 平均 =(Q1+Q2+Q3) / 3.

[0078] Furthermore, the above grouting test simulation is carried out on the rock samples to be grouted in the target strata of Ordovician limestone karst treatment obtained from the drilling holes laid out under different geological conditions within the treatment range, and the average grouting volume per meter of the Ordovician limestone karst strata in the treatment target strata corresponding to different geological conditions can be obtained. Q 平均1 , Q 平均2 , Q 平均3 ···Q 平均n .

[0079] Furthermore, the injectability of karst formations under different geological conditions is evaluated based on the first pore information, the second pore information and the average grouting volume per meter under different geological conditions.

[0080] The present invention determines the average grouting volume per meter by averaging the grouting volumes per meter of a plurality of rock samples to be grouted at different elevations, which is beneficial to subsequently improving the accuracy and reliability of injectability assessment of karst formations.

[0081] The injectability test and analysis device for karst formation provided by the present invention is described below. The injectability test and analysis device for karst formation described below and the injectability test and analysis method for karst formation described above can be referred to each other.

[0082] like Figure 5 As shown, a karst stratum injectability test analysis device includes a sampling module 501, a pore measurement module 502, a grouting module 503 and an evaluation module 504.

[0083] The sampling module 501 is used to obtain core samples of karst strata under different geological conditions in the well field, and to sample the core samples at different heights based on the target treatment layer of the karst stratum to obtain rock samples to be grouting.

[0084] The pore measurement module 502 is used to obtain the first pore information of the rock sample to be grouting before grouting.

[0085] The grouting module 503 is used to obtain the first weight and length of the rock sample to be grouted before grouting, perform a grouting test and initial setting of the slurry on the rock sample to be grouted, obtain the grouted rock sample, and obtain the second weight of the grouted rock sample.

[0086] The grouting module 503 is further used to determine the grouting volume per meter of the rock sample to be grouted based on the first weight, the length of the rock sample and the second weight.

[0087] The pore measurement module 502 is also used to obtain second pore information of the grouting rock sample.

[0088] The evaluation module 504 is used to evaluate the injectability of the karst formation based on the first pore information, the second pore information and the grouting volume per meter.

[0089] The injectability test and analysis device of the karst formation provided by the present invention obtains core samples of the karst formation under different geological conditions of the well field, samples the core samples at different heights based on the target treatment layer of the karst formation, and obtains the rock samples to be grouted; obtains the first pore information of the rock samples to be grouted before grouting; obtains the first weight and the length of the rock sample to be grouted before grouting, performs a grouting test and initial setting of the slurry on the rock sample to be grouted, obtains the grouted rock sample, and obtains the second weight of the grouted rock sample; determines the grouting amount per meter of the rock sample to be grouted based on the first weight, the length of the rock sample and the second weight; obtains the second pore information of the grouted rock sample; and evaluates the injectability of the karst formation based on the first pore information, the second pore information and the grouting amount per meter. The present invention conducts grouting tests on rock samples to be grouted under different geological conditions and compares the pore and fissure characteristics of rock samples before and after grouting, thereby realizing an advance study on the injectability of the target treatment layer, and providing a scientific basis for the subsequent design of ground area treatment schemes, engineering quantity, grouting quantity estimation, treatment effect verification and evaluation. The present invention obtains the consumption of dry materials for grouting per meter of the target stratum for karst strata treatment under different geological conditions by analyzing the first pore information, the second pore information and the grouting volume per meter, clarifies the distribution characteristics of pores and fissures inside the karst strata under different geological conditions, the connectivity status and the filling and blocking of pores and fissures after grouting, realizes the injectability evaluation of Ordovician limestone karst strata under different geological conditions, and can accurately obtain the injectability of Ordovician limestone karst strata in different areas within the treatment range and the measured data related to the grouting effect and intuitive visualization information.

[0090] In one embodiment, the grouting module 503 is used to: place the dried rock sample to be grouted into a test chamber, with the first end and the second end of the test chamber both in an open state; pour slurry into the test chamber from the first end, and when the slurry in the test chamber reaches a preset ratio, close the second end, and continue to pour slurry to increase the pressure in the test chamber until the pressure in the test chamber reaches a set high pressure; stabilize the pressure in the test chamber to maintain the pressure in the test chamber at the set high pressure until the pressure stabilization time exceeds a preset time; after waiting for the slurry in the test chamber to initially set, open the second end to relieve the pressure in the test chamber, remove the cement slurry stone body outside the grouting rock sample, and obtain the rock sample after the slurry has initially set; dry the rock sample after the slurry has initially set to obtain a grouted rock sample.

[0091] In one embodiment, the high pressure is set to include 1.5p~2p, where p is the pressure of the coal seam floor at the target treatment layer to withstand the Ordovician ash water pressure.

[0092] In one embodiment, the sampling module 501 is also used for: observing the detection information set of the well field based on the geological exploration holes and / or the hydrological observation boreholes of the well field, the detection information set including the karst pressure water level elevation, the coal seam floor position and the Ordovician ash top interface position; calculating the thickness of the coal seam floor aquiclude to be modified and the target treatment layer based on the detection information set combined with the requirements of the coal seam floor Ordovician ash pressure water inrush coefficient.

[0093] In one embodiment, the pore measurement module 502 is used to: process, CT scan and SEM scan the grouting rock sample to obtain the porosity of the grouting rock sample; perform three-dimensional modeling on the grouting rock sample based on the CT scanning results of the grouting rock sample to obtain a three-dimensional model of the grouting rock sample, and the three-dimensional model of the grouting rock sample includes the pore distribution characteristics, pore and fracture connectivity and filling status inside the grouting rock sample; obtain the second pore information based on the porosity, pore distribution characteristics, pore and fracture connectivity and filling status of the grouting rock sample.

[0094] In one embodiment, the rock samples to be grouted include rock samples to be grouted at a first elevation, rock samples to be grouted at a second elevation, and rock samples to be grouted at a third elevation. The sampling module 501 is used to: take the target treatment layer as the first elevation, and sample the core sample based on the first elevation to obtain the rock sample to be grouted at the first elevation; take the sum of the target treatment layer and the set height as the second elevation, and sample the core sample based on the second elevation to obtain the rock sample to be grouted at the second elevation; take the difference between the target treatment layer and the set height as the third elevation, and sample the core sample based on the third elevation to obtain the rock sample to be grouted at the third elevation.

[0095] In one embodiment, the per-meter grouting volume of the rock sample to be grouted includes per-meter grouting volumes of multiple rock samples to be grouted at different elevations, and the grouting module 503 is further used to calculate the average per-meter grouting volume of multiple rock samples to be grouted at different elevations to obtain the average per-meter grouting volume. The evaluation module 504 is further used to evaluate the injectability of the karst formation in the area where the core sample is located based on the first pore information, the second pore information and the average per-meter grouting volume.

[0096] Figure 6 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 6As shown, the electronic device may include: a processor (processor) 610 , a communication interface (Communications Interface) 620 , a memory (memory) 630 and a communication bus 640 , wherein the processor 610 , the communication interface 620 , and the memory 630 communicate with each other through the communication bus 640 . The processor 610 can call the logic instructions in the memory 630 to execute the injectability test analysis method of the karst formation, which includes: obtaining core samples of the karst formation under different geological conditions of the well field, sampling the core samples at different heights based on the target treatment layer of the karst formation to obtain rock samples to be grouted; obtaining the first pore information of the rock samples to be grouted before grouting; obtaining the first weight and rock sample length of the rock samples to be grouted before grouting, performing grouting tests and initial setting of slurry on the rock samples to be grouted to obtain grouted rock samples, and obtaining the second weight of the grouted rock samples; determining the grouting volume per meter of the rock samples to be grouted based on the first weight, the rock sample length and the second weight; obtaining the second pore information of the grouted rock samples; and evaluating the injectability of the karst formation based on the first pore information, the second pore information and the grouting volume per meter.

[0097] In addition, the logic instructions in the above-mentioned memory 630 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0098] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the injectability test analysis method of karst formations provided by the above-mentioned methods, the method comprising: obtaining core samples of karst formations under different geological conditions in the well field, sampling the core samples at different heights based on the target treatment layer of the karst formation to obtain rock samples to be grouted; obtaining first pore information of the rock samples to be grouted before grouting; obtaining a first weight and a rock sample length of the rock samples to be grouted before grouting, performing a grouting test and initial setting of the slurry on the rock samples to be grouted to obtain a grouted rock sample, and obtaining a second weight of the grouted rock sample; determining the grouting volume per meter of the rock sample to be grouted based on the first weight, the rock sample length and the second weight; obtaining second pore information of the grouted rock sample; and evaluating the injectability of the karst formation based on the first pore information, the second pore information and the grouting volume per meter.

[0099] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0100] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for analyzing injectability test of karst formations, characterized in that: include: Obtaining core samples of karst strata under different geological conditions in the well field, sampling the core samples at different heights based on the target treatment layer of the karst stratum to obtain rock samples to be grouting; Acquiring first pore information of the rock sample to be grouting before grouting; Obtaining a first weight and a length of the rock sample to be grouted before grouting, performing a grouting test and initial setting of the slurry on the rock sample to be grouted to obtain a grouted rock sample, and obtaining a second weight of the grouted rock sample; Determining the grouting amount per meter of the rock sample to be grouted based on the first weight, the length of the rock sample and the second weight; Acquiring second pore information of the grouting rock sample; The injectability of the karst formation is evaluated based on the first pore information, the second pore information and the grouting volume per meter.

2. The injectability test analysis method of karst formation according to claim 1, characterized in that: The step of performing a grouting test and initial setting of the slurry on the rock sample to be grouted to obtain a grouted rock sample comprises: Putting the dried rock sample to be grouted into a test chamber, wherein the first end of the test chamber and the second end of the test chamber are both in an open state; pouring slurry into the test chamber from the first end, and when the slurry in the test chamber reaches a preset ratio, closing the second end, and continuing to pour the slurry to increase the pressure in the test chamber until the pressure in the test chamber reaches a set high pressure; Stabilizing the pressure of the test chamber to maintain the pressure in the test chamber at the set high pressure until the pressure stabilization time exceeds a preset time; After waiting for the slurry in the test chamber to initially set, the second end is opened to relieve the pressure of the test chamber, and the cement slurry stone body outside the grouting rock sample is removed to obtain the rock sample after the slurry has initially set; The rock sample after the initial setting of the slurry is dried to obtain the grouting rock sample.

3. The injectability test analysis method of karst formation according to claim 2, characterized in that: The set high pressure includes 1.5p~2p, where p is the Ordovician ash water pressure borne by the coal seam floor of the target treatment layer.

4. The injectability test analysis method of karst formation according to claim 1, characterized in that: The target governance level is determined based on the following steps: A detection information set of the well field is observed based on the geological exploration holes of the well field and / or the hydrological observation boreholes of the well field, wherein the detection information set includes the elevation of the karst pressure water level, the position of the coal seam floor and the position of the top interface of the Ordovician limestone; Based on the detection information set and the coal seam floor Ordovician ash pressure-bearing water inrush coefficient requirements, the thickness of the coal seam floor waterproof layer to be transformed and the target treatment layer are calculated.

5. The injectability test analysis method of karst formation according to claim 1, characterized in that: The step of obtaining the second pore information of the grouting rock sample comprises: Processing, CT scanning and scanning electron microscope scanning of the grouting rock sample to obtain the porosity of the grouting rock sample; Based on the CT scanning result of the grouting rock sample, three-dimensional modeling is performed on the grouting rock sample to obtain a three-dimensional model of the grouting rock sample, wherein the three-dimensional model of the grouting rock sample includes pore distribution characteristics, pore-crack connectivity and pore-crack filling status inside the grouting rock sample; The second pore information is obtained based on the porosity of the grouting rock sample, the pore distribution characteristics, the pore-fracture connectivity state, and the pore-fracture filling state.

6. The injectability test analysis method of karst formation according to claim 1, characterized in that: The rock samples to be grouted include rock samples to be grouted at a first elevation, rock samples to be grouted at a second elevation, and rock samples to be grouted at a third elevation. The rock samples to be grouted are sampled at different heights based on the target treatment layer of the karst formation to obtain the rock samples to be grouted, including: Taking the target treatment layer as a first elevation, sampling the core sample based on the first elevation to obtain a rock sample to be grouted at the first elevation; Taking the sum of the target treatment layer and the set height as the second elevation, sampling the core sample based on the second elevation to obtain the rock sample to be grouted at the second elevation; The difference between the target treatment layer and the set height is taken as the third elevation, and the core sample is sampled based on the third elevation to obtain the rock sample to be grouting at the third elevation.

7. The injectability test analysis method of karst formation according to claim 1, characterized in that: The grouting amount per meter of the rock sample to be grouted includes grouting amounts per meter of a plurality of rock samples to be grouted at different elevations. After determining the grouting amount per meter of the rock sample to be grouted based on the first weight, the length of the rock sample and the second weight, the method further includes: Calculate the average of the grouting amount per meter of the plurality of rock samples to be grouted at different elevations to obtain the average grouting amount per meter; The injectability of the karst formation in the area where the core sample is located is evaluated based on the first pore information, the second pore information and the average grouting volume per meter.

8. A karst stratum injectability test and analysis device, characterized in that: Includes sampling module, pore measurement module, grouting module and evaluation module: The sampling module is used to obtain core samples of karst strata under different geological conditions in the well field, and to sample the core samples at different heights based on the target treatment layer of the karst stratum to obtain rock samples to be grouting; The pore measurement module is used to obtain the first pore information of the rock sample to be grouting before grouting; The grouting module is used to obtain the first weight and length of the rock sample to be grouted before grouting, perform a grouting test and initial setting of the slurry on the rock sample to be grouted, obtain a grouted rock sample, and obtain a second weight of the grouted rock sample; The grouting module is further used to determine the grouting amount per meter of the rock sample to be grouted based on the first weight, the length of the rock sample and the second weight; The pore measurement module is also used to obtain second pore information of the grouting rock sample; The evaluation module is used to evaluate the injectability of the karst formation based on the first pore information, the second pore information and the grouting volume per meter.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the injectability test analysis method for karst formations as described in any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the injectability test analysis method for karst formations as described in any one of claims 1 to 7 is implemented.

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